Compact MR write structure

ABSTRACT

A compact write element for magnetically recording data on a magnetic medium and methods for making the same. The write element includes a conductive shield layer, an insulating write gap layer, a pole pedestal, a coil, and a conductive pole layer, with some embodiments further including a backgap. The pole pedestal, coil, and in some embodiments the backgap, constitute a self-aligned array of components that may be formed with a single masking operation to allow for very tight tolerances between the components for a shorter yoke length. The pole layer of the present invention is substantially flat and parallel to the conductive shield layer, providing for a shorter stack height. The present invention includes incorporation of the compact write element in both a read/write head and a magnetic data storage and retrieval system.

BACKGROUND OF THE INVENTION

This invention relates generally to magnetic data storage systems, moreparticularly to magnetoresistive read/write heads, and most particularlyto an especially compact write structure.

Magnetic disk drives are used to store and retrieve data for digitalelectronic apparatuses such as computers. In FIGS. 1A and 1B, a magneticdisk data storage system 10 includes a sealed enclosure 12, a disk drivemotor 14, and a magnetic disk, or media, 16 supported for rotation by adrive spindle S1 of motor 14. Also included are an actuator 18 and anarm 20 attached to an actuator spindle S2 of actuator 18. A suspension22 is coupled at one end to the arm 20, and at its other end to aread/write head or transducer 24. The transducer 24 typically includesan inductive write element with a sensor read element (both of whichwill be described in greater detail with reference to FIG. 2A). As themotor 14 rotates the magnetic disk 16, as indicated by the arrow R, anair bearing is formed under the transducer 24 causing it to liftslightly off of the surface of the magnetic disk 16, or, as it issometimes termed in the art, to “fly” above the magnetic disk 16. Withthe arm 20 held stationary, data bits can be read along acircumferential “track” as the magnetic disk 16 rotates. Further,information from concentric tracks can be read from the magnetic disk 16as the actuator 18 causes the transducer 24 to pivot in an arc asindicated by the arrows P. The design and manufacture of magnetic diskdata storage systems is well known to those skilled in the art.

FIG. 2A depicts a magnetic read/write head 24 including a read element26 and a write element 28. Edges of the read element 26 and writeelement 28 also define an air bearing surface ABS, in a plane 29, whichcan be aligned to face the surface of the magnetic disk 16 (see FIGS. 1Aand 1B). The read element 26 includes a first shield 30, an intermediatelayer 32, which functions as a second shield, and a read sensor 34 thatis located within a dielectric medium 35 between the first shield 30 andthe second shield 32. The most common type of read sensor 34 used in theread/write head 24 is the magnetoresistive (AMR or GMR) sensor which isused to detect magnetic field signals from a magnetic medium throughchanging resistance in the read sensor.

The write element 28 is typically an inductive write element whichincludes the intermediate layer 32, which functions as a first pole, anda second pole 38. A first pole pedestal 42 may be connected to a firstpole tip portion 43 of the first pole 32, and a second pole pedestal 44may be connected to the second pole tip portion 45 of the second pole38. The first pole 32 and the second pole 38 are attached to each otherby a backgap 40 located distal to their respective pole tip portions, 43and 45. The first pole 32, the second pole 38, and the backgap 40collectively form a yoke 41 together with the first pole pedestal 42 andthe second pole pedestal 44, if present. The area around the first poletip portion 43 and the second pole tip portion 45 near the ABS issometimes referred to as the yoke tip region 46. A write gap 36 isformed between the first pole pedestal 42 and the second pole pedestal44 in the yoke tip region 46. The write gap 36 is formed of anon-magnetic electrically insulating material. This non-magneticmaterial can be either integral with (as is shown here) or separate froma first insulation layer 47 that lies between the first pole 32 and thesecond pole 38, and extends from the yoke tip region 46 to the backgap40.

Also included in write element 28 is a conductive coil layer 48, formedof multiple winds 49. The conductive coil layer 48 is positioned withina coil insulation layer 50 that lies above the first insulation layer47. The first insulation layer 47 thereby electrically insulates thecoil layer 48 from the first pole 32, while the coil insulation layer 50electrically insulates the winds 49 from each other and from the secondpole 38. In some prior art fabrication methods, the formation of thecoil insulation layer includes a thermal curing of an electricallyinsulating material, such as photoresistive “photoresist” material.

FIG. 2B shows a plan view of the read/write head 24 taken along line2B—2B of FIG. 2A. This view better illustrates how the coil layer 48 ofwrite element 28 is configured as a spiral with each wind 49 passingaround the backgap 40 and beneath the second pole 38 in the regionbetween the backgap 40 and the second pole tip region 45. Because of themagnetic properties of the yoke 41, when a write current is passedthrough coil layer 48 a magnetic flux is induced in the first and secondpoles 32 and 38. The write gap 36, being non-magnetic, allows themagnetic flux to fringe out from the yoke 41, thus forming a fringinggap field. Data may be written to the magnetic disk 16 by placing theABS of read/write head 24 proximate to the magnetic disk 16 such thatthe fringing gap field crosses the surface of the magnetic disk 16.Moving the surface of the magnetic disk 16 through the fringing gapfield causes a reorientation of the magnetic domains on the surface ofthe magnetic disk 16. As the magnetic disk 16 is moved relative to thewrite element 28, the write current in coil layer 48 is varied to changethe strength of the fringing gap field, thereby encoding data on thesurface of the magnetic disk 16 with a corresponding variation oforiented magnetic domains.

Returning to FIG. 2A, a number of parameters that influence theperformance of the write element 28 are also shown. The first of theseparameters is the yoke length YL, sometimes defined as the distance fromthe backgap 40 to the first pole pedestal 42. A shorter yoke length YLfavors higher data recording rates as it tends to reduce the flux risetime. The flux rise time is a measure of the time lag between the momenta current passed through coil layer 48 reaches its maximum value and themoment the fringing flux field between the first pole 32 and the secondpole 38 reaches its maximum. Ideally, the response would beinstantaneous, but various factors such as the physical dimensions andthe magnetic properties of the yoke 41 cause the flux rise time toincrease. A shorter flux rise time is desirable both to increase therate with which data may be written to a magnetic disk 16, and also todecrease the length of, and the spacing between, data bits on themagnetic disk 16. Shorter data bits more closely spaced together isdesirable for increasing the total storage capacity of the magnetic disk16.

Write elements according to the prior art are manufactured throughcommon photolithography techniques well known in the art involvingrepeated cycles of masking with “photoresist,” depositing layers ofvarious materials, followed by stripping away remaining photoresist.Each cycle through this process typically fabricates one element of thefinal structure. Consequently, tolerance for mask misalignment must beaccounted for in the designs for these devices. In particular, prior artwrite elements leave a separation of at least 4 microns between polepedestals 42 and 44 and the coil layer 48. A similar gap of at least 4microns is found between the backgap 40 and the coil layer 48. Theseseparations add extra length to the yoke length YL that increases theflux rise time and hinders write performance.

Another parameter of the write element 28 is the stack height SH,sometimes defined as the distance between the top surface of the firstpole 32 and the top of the second pole 38, as shown in FIG. 2A. Thestack height SH is influenced by the apex angle α, which characterizesthe angle of the slope region of the second pole 38 near the yoke tipportion 46 measured relative to a horizontal reference such as theintermediate layer 32. Increasing the stack height SH makes it difficultto control the track width within narrow set tolerances, decreasing theproduction yield. Consequently, increasing the apex angle α has theeffect of increasing the stack height SH to the detriment of writeperformance.

A further problem associated with the apex angle α relates to themagnetic properties of the second pole 38. Increasing the apex angle αincreases the topography over which the second pole 38 must be formednear the yoke tip portion. The second pole 38 is typically formed bysputtering or plating, techniques well suited for producing flat layers,but not as well suited for forming complex surfaces. Consequently, afurther problem associated with the apex angle α is lower productionyields resulting from the difficulties encountered in producinguniformity in the second pole 38, especially in the slope region. Stillanother problem associated with apex angle α relates to the magneticproperties of the second pole 38 in the slope region, which will bedescribed with reference to FIGS. 3A-3C.

The trend towards higher density recording in the disk drive industryhas forced a number of materials changes in the components of thedrives, which has, in turn, created additional problems. In particular,in order to achieve higher data densities on the surface of the magneticdisk 16, the traditional magnetic media have not been found to besufficient. To obtain smaller bits it has been necessary to developrecording media with higher magnetic coercivities. To write to amagnetic medium with a higher magnetic coercivity requires that thewrite element 28 produce a stronger fringing flux field. To produce astronger fringing flux field further requires the use of magneticmaterials capable of carrying larger magnetic fluxes. In other words,for high density recording applications, new materials for components ofthe yoke 41 need to have high magnetic saturation (Bs) values.

Permalloy, a nickel alloy containing 20% by weight of iron, is thematerial most frequently used to form magnetic components of prior artrecording devices. However, Permalloy has an unacceptably low Bs for usein high density recording. Consequently, designers of magnetic recordingdevices have turned to high Bs materials such as nickel alloyscontaining between 35% and 55% by weight of iron. Replacing Permalloywith higher Bs materials would be a simple matter except for the issueof magnetostriction.

When a material with a non-zero magnetostriction is subjected to astress, a magnetic field is produced in response. Similarly, when such amaterial is placed in a magnetic field, a stress in the materialdevelops. Permalloy has been an advantageous material in magneticrecording devices because it has a magnetostriction value of nearlyzero. The higher Bs materials, on the other hand, exhibit much highermagnetostriction values. These higher magnetostriction values createadditional problems for high density recording applications.

FIGS. 3A-3C illustrate how the apex angle α coupled with high Bsmaterials is problematic for high density recording. FIG. 3A shows aplan view of the second pole 38 showing a typical arrangement ofmagnetic domains 51 as they appear on the top surface of the second pole38 when fabricated from high Bs materials. Arrows within the magneticdomains 51 indicate the orientations of the domains' magnetizations.Through much of the body of the second pole 38 the magnetic fields ofthe domains 51 are favorably oriented perpendicular to the long axis ofthe second pole 38. However, in the second pole tip region 45 themagnetization of domains 51 are aligned parallel to the long axis of thesecond pole 38. In the intervening slope region, the magnetic domainsare disordered.

FIG. 3B shows a cross-sectional view along the line 3B—3B of FIG. 3A.Similarly, FIG. 3C is an ABS view along the line 3C—3C of FIG. 3B. InFIG. 3C the orientations of the magnetization within the magneticdomains are represented by dots and circled dots. Dots and circled dotsshow, respectfully, orientations into and out from the plane of thedrawing. From FIGS. 3A-3C it can be seen that within the second pole tipregion 45 the magnetic domains form a layered structure withmagnetization orientations perpendicular to the ABS. This layeredstructure is sometimes referred to as a striped domain pattern.

It has been found that with increasing apex angle α the stresses in themagnetic film in the slope region of the second pole 38 also increase.Some of the stress in the magnetic film is inherent from themanufacturing process. Additional stresses may increase during theoperation of the read/write head 24 as heat is generated within thedevice and differences in coefficients of thermal expansion betweendifferent materials create minor dimensional changes. The retention ofphotoresist as an insulator in some prior art devices is especiallytroublesome in this regard, as photoresist has a relatively largecoefficient of thermal expansion. Consequently, photoresist retainedbeneath the second pole 38 has the effect, when the device is in use, ofcreating especially large stresses in the slope region of the secondpole 38. Therefore, since the effect of magnetostriction is tocounteract a stress with a magnetic field, undesirable magnetic fieldsin the slope region of the second pole 38 tend to increase both as theapex angle α increases and when photoresist is retained beneath thesecond pole 38. These undesirable magnetic fields give rise to thestriped domain pattern and disordered domains.

The striped domain pattern in the second pole tip region 45 and thedisordered domains in the slope region are detrimental to theperformance of the write element 28. In particular, these misorienteddomains resist changes in the magnetization of the yoke 41.Consequently, when a write current is introduced into the coil layer 48and a magnetic field is induced in the yoke 41, the flux rise time islengthened by the resistance to change of the misoriented domains.Longer flux rise times and poorer performance are, therefore, associatedwith an increasing apex angle α and with the use of retained photoresistbeneath the second pole 38.

FIG. 4 shows a more desirable arrangement of magnetic domains 51 for thesecond pole 38. Arrows within the magnetic domains 51 indicate magneticorientation. With such an idealized arrangement, the magnetization ofthe yoke 41 should respond more quickly to changes in the write currentin coil layer 48, thus improving the write performance of the writeelement 28 by reducing the flux rise time.

Thus, what is desired is a write element with a substantially flatsecond pole and a shorter yoke length YL. Such a write element wouldeliminate the apex angle α, have a smaller stack height SH, and wouldnot have the misoriented magnetic domain problems associated with theslope region. Further, it is desired to be able to fabricate a writeelement without retaining any photoresist as an insulator. It isadditionally desired that fabrication of such a write element should beinexpensive, quick, and simple.

SUMMARY OF THE INVENTION

The present invention provides a compact structure for a write elementof a read/write head of a magnetic data storage device. The structureincludes both a substantially flat second pole, significantly less spacebetween the coil and the backgap, and significantly less space betweenthe coil and the pole pedestal. Additionally, a method for thefabrication of such a compact write element is provided.

In an embodiment of the present invention a compact magnetic writestructure is provided comprising a conductive shield layer defining aplane, an insulating write gap layer at least partially covering theconductive shield layer, a self-aligned array comprising a conductivepole pedestal and a coil, and a conductive pole layer disposed over thecoil and contacting the pole pedestal. The conductive pole layer definesa plane substantially parallel to the plane of the conductive shieldlayer. The separation between the pole pedestal and the coil is nogreater than about 2.0 microns. A further embodiment of the presentinvention includes both a backgap opening in the insulating write gaplayer, and a backgap as part of the self-aligned array. The backgapcontacts the conductive shield through the backgap opening.

Additional embodiments of the present invention are directed to acompact MR read/write head that further includes a MR read element. Theread element itself comprises two conductive shields separated by aninsulator layer in which the MR sensor is disposed, and one of theconductive shields also serves as the first pole of the compact magneticwrite structure. Still other embodiments are directed to a magnetic datastorage and retrieval system additionally incorporating a magneticmedium and a medium support, where the medium support is capable ofsupporting the magnetic medium and moving it in relation to theread/write head.

This compact magnetic write structure is advantageous because itprovides a substantially flat second pole without a slope region.Eliminating the slope region serves to both reduce the magnetostrictiveinduced resistance to magnetization changes in the yoke, and to reducethe stack height. Both of these changes reduce the flux rise time andimprove writing performance. The structure is further advantageous forlimiting the separation between the pole pedestal and the coil to nogreater than about 2.0 microns, thereby reducing the yoke length forfarther writing performance enhancement. The embodiment in which theseparation between the backgap and the coil to no greater than about 2.0microns is similarly advantageous for further reducing the yoke length.Still another advantage is the ability to fabricate the structurewithout retaining photoresist as an insulator. This is also advantageousfor lowering the flux rise time by reducing unwanted stresses in high Bsmagnetic materials caused by large mismatches in coefficients of thermalexpansion.

Yet another embodiment of the present invention is directed to a methodfor manufacturing a magnetic write structure. The method includesproviding a substrate including a conductive shield layer and aninsulating write gap layer. The conductive shield layer defines a plane,and the insulating write gap layer at least partially covers theconductive shield layer. The method further includes forming over thesubstrate a self-aligned array comprising a plurality of componentsincluding a conductive pole pedestal and a coil. The pole pedestal andthe coil contact the write gap layer, and the separation between thepole pedestal and the coil is no greater than about 2.0 microns.Additionally, the method includes forming a conductive pole layer overthe self-aligned array. The pole layer is in contact with the polepedestal and defines a plane that is substantially parallel to the planeof the conductive shield layer. The present invention further includes aplanarization step prior to the formation of the pole layer helping toensure that the plane of the pole layer is substantially parallel to theplane of the conductive shield layer.

Additional embodiments of this invention are directed to a method formanufacturing a magnetic write structure in which the insulating writegap layer is provided with a backgap opening, the plurality ofcomponents of the self-aligned array further includes a conductivebackgap, and the conductive backgap is disposed above and contacts theconductive shield layer through the backgap opening. The separationbetween the backgap and the coil in these embodiments is no greater thanabout 2.0 microns. In still other embodiments a seed layer is formedabove and in contact with the insulating write gap layer.

These methods for manufacturing magnetic write structures areadvantageous because they incorporate a self-aligned array. Aself-aligned array allows the pole pedestal and the coil to be formedwith the same mask, thereby allowing these two components to be formedas close together as masking technology will allow without having toleave excess space between them to allow for the possible misalignmentof successive masks. Embodiments incorporating a backgap also takeadvantage of the self-aligned array to minimize the space between thebackgap and the coil. A further advantage of the self-aligned array isthat it reduces the total number of masking operations needed to form amagnetic write structure, thus saving time and reducing manufacturingcosts.

Another advantage of this manufacturing method derives from theplanarization step preceding the formation of the pole layer. Theplanarization achieves three important goals. The first goal is toexpose the backgap and the second pole pedestal. The second is to reducethe overall stack height of the finished write structure, improving thewrite performance of the finished device. The third goal served by theplanarization step is that the pole layer formed over the planarizedsurface is itself substantially flat and substantially parallel to theplane of the conductive shield layer. This serves to simplify thegeometry of the pole layer, thereby reducing or substantiallyeliminating domain striping and further improving write performance ofthe finished device.

These and other advantages of the present invention will become apparentto those skilled in the art upon a reading of the following descriptionsof the invention and a study of the several figures of the drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be readily understood by the followingdetailed description in conjunction with the accompanying drawings, andlike reference numerals designate like elements.

FIG. 1A is a partial cross-sectional elevation view of a magnetic datastorage system;

FIG. 1B is a top plan view along line 1B—1B of FIG. 1A;

FIG. 2A is a cross-sectional view of a read/write head according to theprior art;

FIG. 2B is a top plan view along line 2B—2B of FIG. 2A;

FIG. 3A is a top plan view showing a typical arrangement of magneticdomains at the surface of a prior art second pole;

FIG. 3B is a cross-sectional view along the line 3B—3B of FIG. 3A;

FIG. 3C is an ABS view along the line 3C—3C of FIG. 3B;

FIG. 4 is a top plan view showing a more desirable arrangement ofmagnetic domains at the surface of the second pole sought to be achievedby the present invention;

FIG. 5 is a cross-sectional view of a read/write head according to anembodiment of the present invention;

FIGS. 6A-6E are cross-sectional views of a read/write head at variousstages of fabrication, according to an embodiment of the presentinvention;

FIG. 6F is a top plan view along the line 6F in FIG. 6E showing therelationship of the components of a self-aligned array according to anembodiment of the present invention;

FIGS. 6G-6M are further cross-sectional views of a read/write head atvarious stages of fabrication, according to an embodiment of the presentinvention;

FIG. 6N is a top plan along the line 6N in FIG. 6M illustrating thenarrowing of the second pole pedestal according to an embodiment of thepresent invention; and

FIGS. 6O-6R are further cross-sectional views of a read/write head atvarious stages of fabrication, according to an embodiment of the presentinvention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1A, 1B, 2A, 2B, 3A-3C, and 4 were discussed with reference to theprior art.

FIG. 5 is a cross-sectional view of a read/write head 50 according to anembodiment of the present invention, including a read element 26 and awrite element 60. Edges of the read element 26 and write element 60 alsodefine an air bearing surface ABS, in a plane 29, which can be alignedto face the surface of the magnetic disk 16. The read element 26includes a first shield 30, a conductive shield layer 32, whichfunctions as a second shield, and a read sensor 34 that is a conductivepole layer disposed over said pole pedestal and said coil and includinga pole tip portion contacting said pole pedestal, said conductive polelayer including said pole tip portion defining a plane which issubstantially parallel to said plane of said conductive shield layer.

The write element 60 includes conductive shield layer 32, whichfunctions as a first pole, and a second pole 52. The conductive shieldlayer 32 includes a first pole tip portion 43, and the second pole 52includes a second pole tip portion 56. A second pole pedestal 58 isconnected to the second pole tip portion 56 of the second pole 52. Theconductive shield layer 32 and the second pole 52 are joined together bya backgap 62 located distal to their respective pole tip portions, 43and 56. The conductive shield layer 32, the second pole 52, the backgap62, and the second pole pedestal 58 collectively form a yoke 64.Additional embodiments of the present invention may also include a firstpole pedestal (not shown) that may be connected to the first pole tipportion 43 of the conductive shield layer 32. The components of the yoke64 may be formed from any electrically conductive material, however,high Bs materials such as CoNiFe alloys and nickel alloys containingiron in the 35% to 55% by weight range, such as Ni-35% Fe, Ni-45% Fe,and Ni-55% Fe work well.

The area within the space enclosed by the yoke 64 contains a write gaplayer 66, a coil 68 comprising individual winds 69, wind insulators 70,a pole pedestal insulator 72, a backgap insulator 74, and a second poleinsulation layer 76. The write gap layer 66 is a continuous filmextending from the ABS to the backgap 62. The write gap layer 66separates the first pole tip portion 43 from the second pole pedestal58, and the conductive shield layer 32 from the coil 68. The polepedestal insulator 72 isolates the second pole pedestal 58 from thenearest wind 69′ of coil 68. Similarly, the backgap insulator 74isolates the backgap 62 from the nearest wind 69″ of coil 68. The windinsulators 70 separate the individual winds 69 of coil 68 from oneanother. The second pole insulation layer 76 insulates the second pole52 from the coil 68. The coil 68 may be made from any conductivematerial, however, copper works well. Likewise, the write gap layer 66,the wind insulators 70, the pole pedestal insulator 72, the backgapinsulator 74, and the second pole insulation layer 76, may be made fromany non-magnetic electrically insulating material such as alumina(Al₂O₃) or silica (SiO₂).

FIGS. 6A-6R illustrate a method for manufacturing a magnetic writestructure according to the present invention. FIG. 6A shows the startingpoint of the process. A substrate 80 is provided including a supportmember 82, a conductive shield layer 32, and an insulating write gaplayer 66 at least partially covering the conductive shield layer 32.Embodiments including a read element 26 will further include within thesubstrate 80 a first shield 30, and a read sensor 34 located within adielectric medium 35. The conductive shield layer 32 functions as asecond shield for read element 26.

The support member 82 is a base on which a plurality of write structuresmay be assembled. It should be thick enough to provide good mechanicalsupport for handling. The support member 82 should be substantially flatand chemically inert so that substantially flat layers may be formedabove it, and so that those layers do not chemically react with it.Ideally, the support member 82 should also be fairly inexpensive.Silicon wafers are known to work well for support member 82.

The materials and fabrication methods for the first shield 30, the readsensor 34, and the dielectric medium 35 are well known in the art. Theconductive shield layer 32 may be formed from any electricallyconductive material, however, high Bs materials such as CoNiFe alloysand nickel alloys containing iron in the 35% to 55% by weight range,such as Ni-35% Fe, Ni-45% Fe, and Ni-55% Fe work well for producingwrite elements for high density recording applications. The conductiveshield layer 32 may be formed by any number of common fabricationtechniques well known in the art such as plating. The insulating writegap layer 66 may be formed of any electrically insulating material, withalumina and silica commonly used, and may be formed by any well knowndeposition technique such as chemical vapor deposition (CVD). A backgapopening 85 in the insulating write gap layer 66 is provided in someembodiments. The backgap opening may be formed by common techniques wellknown in the art such as masking followed, for example, by reactive ionetching (RIE) or wet etching.

FIG. 6B shows the formation of a seed layer 86 above and in contact withthe insulating write gap layer 66. The seed layer also covers theconductive shield layer 32 where the conductive shield layer 32 isexposed by an opening in the insulating write gap layer 66. The seedlayer 86 may improve the adhesion of subsequent metallic layers, andalso forms a useful etch stop when reactive ion etching (RIE) is used toremove subsequently formed insulating layers that are not part of thefinal structure. The seed layer 86 is typically deposited by sputteringa material having the same composition as that of film to be plated. Thethickness of the seed layer 86 is about 0.1 microns to about 0.5 micronsthick.

Formed above the seed layer 86 is a first insulation layer 88. The firstinsulation layer 88 may be formed of any electrically insulatingmaterial, such as silica, and may be formed by any suitable depositiontechnique such as CVD. The first insulation layer 88 should be at leastas thick as the coil 68 will ultimately be, in the range of 0.5 micronsto 2.0 microns.

FIG. 6C shows a first mask 90 disposed above and in contact with thefirst insulation layer 88. The first mask 90 is formed of photoresistand patterned by photolithography techniques well known in the art. Thefirst mask 90 includes openings to expose the first insulation layer 88.These openings are situated above locations where portions of the firstinsulation layer 88 will subsequently be removed to create voids. Thevoids to be formed in the first insulation layer 88 will ultimately befilled with conductive materials to form the individual winds 69 of coil68, and the second pole pedestal 58. In some embodiments a void in thefirst insulation layer 88 will also be created to allow for thesubsequent formation of the backgap 62.

FIG. 6D illustrates a stage in the construction of the magnetic writestructure after voids in the first insulation layer 88 have been formed.The voids may be created by RIE, for example, using the seed layer 86 asan etch stop. FIG. 6E shows the partially constructed magnetic writestructure after the remnants of the first mask 90 have been removed byany appropriate stripping technique well known to the photolithographyarts. The first insulation layer 88 is left with a pole pedestal void92, at least one coil void 94, and in some embodiments a backgap void96. FIG. 6F shows a plan view of the pattern of voids created in thefirst insulation layer 88 as viewed along the line 6F in FIG. 6E.

FIGS. 6G-6I illustrate the formation of coil 68, beginning with theformation of a second mask 98 having an aperture, wherein the apertureexposes at least one coil void 94. Except for the coil voids 94 exposedby the aperture, the second mask 98 otherwise completely covers thesurface of the magnetic write structure being created. The second mask98 is formed of photoresist and patterned by well known photolithographytechniques.

FIG. 6H further illustrates the formation of coil 68. As previouslynoted, coil 68 is comprised of individual winds 69. The individual winds69 are formed of an electrically conductive material such as copperwithin the coil voids 94 by any suitable technique, for example, byplating. The individual winds 69, once formed, should be about 0.5microns to about 2.0 microns in thickness. Following the formation ofthe individual winds 69, the second mask 98 may be removed by anyappropriate stripping technique. The removal of the second mask 98completes the formation the coil 68. The partially constructed magneticwrite structure is shown in FIG. 61 following the removal of second mask98.

FIGS. 6J-6L show the formation of the second pole pedestal 58, and insome embodiments the backgap 62. In FIG. 6J a third mask 100 is formedof photoresist and patterned by photolithography techniques. The thirdmask 100 is patterned to cover the coil 68. An electrically conductivematerial, preferably with a high Bs value, is formed within the polepedestal void 92, and in some embodiments the backgap void 96. This maybe accomplished by any suitable technique known in the art, for example,by plating. The material deposited in the pole pedestal void 92, and insome embodiments the material deposited in the backgap void 96, shouldfill these voids to a thickness in the range of about 0.5 microns toabout 2.0 microns. Examples of high Bs materials include nickel alloyscontaining iron in the 35% to 55% by weight range, such as Ni-35% Fe,Ni-45% Fe, and Ni-55% Fe. FIG. 6K shows the partially constructedmagnetic write structure following the completion of this operation.FIG. 6K includes a second pole pedestal 58 and a backgap 62.

FIG. 6L illustrates the partially constructed magnetic write structurefollowing the completion of the self-aligned array 102, comprising thecoil 68, the second pole pedestal 58, and in some embodiments thebackgap 62. The self-aligned array 102 is completed by removing thethird mask 100, removing the remnants of the first insulation layer 88,and by removing the seed layer 86 from everywhere except where it iscovered by the individual winds 69, the second pole pedestal 58, and thebackgap 62. The seed layer 86 must be removed from these locationsbecause otherwise it would create electrical short circuits. The thirdmask 100 may be removed by any appropriate stripping technique. Theremnants of the first insulation layer 88 may be removed by any suitabletechnique such as ion milling. Lastly, the portions of the seed layer 86exposed by the removal of the remnants of the first insulation layer 88may themselves be removed by any suitable process such as RIE.

In some embodiments of the present invention forming the second polepedestal 58 further involves narrowing the width of the second polepedestal 58. Narrowing the width of the second pole pedestal 58 isdesirable for narrowing the trackwidth the magnetic write structureultimately will produce when used to transfer data to a magnetic disk16. Narrowing the second pole pedestal 58 is shown in FIGS. 6M-6O. InFIG. 6M a fourth mask 104 is formed above and in contact with the coil68. The fourth mask 104 is formed of photoresist and patterned byphotolithography techniques. FIG. 6N shows a plan view of the partiallycompleted magnetic write structure as viewed along line 6N in FIG. 6M.This figure shows the initial width W of the second pole pedestal 58prior to the narrowing process, and the final width W′ following thecompletion of the narrowing process. The width of the second polepedestal 58 may be reduced from W to W′, for example, by low angle ionmilling. Narrowing the second pole pedestal 58 is completed by removingthe fourth mask 104 by any appropriate stripping technique. FIG. 6Oshows the partially completed magnetic write structure after theformation of the self-aligned array 102, and in some embodiments afterthe second pole pedestal 58 has been narrowed from a width of W to awidth of W′.

FIG. 6P-shows the formation of a second insulating layer 106 above andcovering the self-aligned array. The second insulating layer 106 fillsthe spaces between individual winds 69 forming the wind insulators 70shown in FIG. 5. The second insulating layer 106 also fills the spacebetween the second pole pedestal 58 and its nearest individual wind 69′,and the space between the backgap 62 and its nearest individual wind 69″forming, respectfully, the pole pedestal insulator 72 and the backgapinsulator 74 shown in FIG. 5. The second insulating layer 106 may beformed of any electrically insulating material such as alumina orsilica, and may be deposited by any suitable technique such as CVD.

The second insulating layer 106 is planarized to expose the second polepedestal 58, and in some embodiments the backgap 62. FIG. 6Q shows thepartially completed magnetic write structure following the planarizationof the second insulating layer 106. Following planarization the secondpole pedestal 58 has a first surface 108, the backgap 62 has a firstsurface 110, and the second insulating layer 106 has a first surface112. All three of these surfaces are substantially coplanar with eachother. Planarization may be accomplished by any suitable technique suchas chemical mechanical polishing (CMP).

A conductive pole layer 52 is formed above and in contact with thesecond insulating layer 106, the second pole pedestal 58, and thebackgap 62 as shown in FIG. 6R. Conductive pole layer 52 should besubstantially parallel to the plane of conductive shield layer 32, andno more than 10° away from parallel. The conductive pole layer 52 may beformed from any electrically conductive material, however, high Bsmaterials such as CoNiFe alloys and nickel alloys containing iron in the35% to 55% by weight range, such as Ni-35% Fe, Ni-45% Fe, and Ni-55% Fework well for producing write elements for high density recordingapplications. The conductive pole layer 52 may be formed by any suitablefabrication technique such as plating. FIG. 6R also shows the plane 29of the air bearing surface (ABS) that must be exposed to make themagnetic write structure operable. This may be accomplished by anysuitable method such as grinding and lapping.

In summary, the present invention provides structures and methods forproviding a magnetic recording device that can be used in high datadensity applications with improved write performance. The invention hasbeen described herein in terms of several preferred embodiments. Otherembodiments of the invention, including alternatives, modifications,permutations and equivalents of the embodiments described herein, willbe apparent to those skilled in the art from consideration of thespecification, study of the drawings, and practice of the invention. Theembodiments and preferred features described above should be consideredexemplary, with the invention being defined by the appended claims,which therefore include all such alternatives, modifications,permutations and equivalents as fall within the true spirit and scope ofthe present invention.

What is claimed is:
 1. A magnetic write structure comprising: aconductive shield layer defining a plane; an insulating write gap layerat least partially covering said conductive shield layer; a self-alignedarray comprising a conductive pole pedestal and a coil, said coilcomprising a plurality of winds, said pole pedestal and said coilcontacting said write gap layer, wherein a separation between said polepedestal and a first of said winds of said coil is no greater than about2.0 microns; and a conductive pole layer disposed over said polepedestal and said coil and including a pole tip portion contacting saidpole pedestal, said conductive pole layer including said pole tipportion defining a plane which is substantially parallel to said planeof said conductive shield layer.
 2. The magnetic write structure asrecited in claim 1 wherein said insulating write gap layer is providedwith a backgap opening, and wherein said self-aligned array furthercomprises a backgap contacting said conductive shield through saidbackgap opening.
 3. The magnetic write structure as recited in claim 2wherein the separation between said backgap and said coil is no greaterthan about 2.0 microns.
 4. The magnetic write structure as recited inclaim 1 wherein an angle formed between said plane of said conductivepole layer and said plane of said conductive shield layer is less thanabout 10°.
 5. The magnetic write structure as recited in claim 1 whereina width of said conductive pole pedestal is in the range of about 0.1microns to about 1.0 microns.
 6. A magnetic write structure comprising:a conductive shield defining a plane; an insulating write gap layer atleast partly covering said conductive shield layer; a self-aligned arraycomprising a conductive pole pedestal and a coil said pole pedestal andsaid coil contacting said write gap layer, said pole pedestal and saidcoil having a separation therebetween no greater than about 2.0 microns;and a conductive pole comprising a pole tip portion, a portion situatedover said coil, and a portion situated over said separation between saidpole pedestal and said coil, wherein a slope of said conductive poleportion over said separation is less than about 10°.
 7. A magnetic writestructure comprising: a conductive shield defining a plane; aninsulating write gap layer at least partly covering said conductiveshield layer; a self-aligned array comprising a conductive pole pedestaland a coil comprising a plurality of winds, said pole pedestal and saidcoil contacting said write gap layer; a pole pedestal insulator situatedin a separation between said pole pedestal and a wind nearest said polepedestal; and a conductive pole comprising a pole tip portion, a portionsituated over said coil, and a portion situated over said pole pedestalinsulator, and a portion over the pole pedestal, wherein a slope of saidconductive pole portion over said pole pedestal insulator is less thanabout 10°.
 8. The magnetic write structure of claim 7 wherein theseparation between said pole pedestal and said nearest wind is less thanabout 2.0 microns.